If all countries convert their money to cryptocurrency, in principle there may be various benefits: simple efficiency of instant global electronic transactions, preventing forgery, recording and monitoring better transactions, no printing machines, etc.

But, there are major losses here. The first is that decentralization will be eliminated by "central digital currencies" and this will even be more centralized than the existing system. And another disadvantage is privacy. Cash is anonymous, giving people some freedom to spend money without having to worry about explaining their actions. But, crypto money released by the government will remove all privacy from your expenses.